ID this Live Rock Inhabitant please

I have about 5 or so of these guys on my live rock and did not notice them until today when I saw the arms or tenticles out for the first time. Their bodies or shell seems to be implanted in the rock and then small clear to white tenticles come out of the center.

 

don't see it in pic but from what you say it sounds like a spagettie worm

 

It's the thing in the center of the pick on the rock. I circled it in red.

 

do you have a pic with the tenticals hanging out

 

is there one to the right of that circled one too? are it's tentacles out in that pic? do the tentacles only come out at night?

 

Yes there is one off to the right of the circled one and the tentacles are out on it. They come out durring the day not sure about night time.

Here is this one with the tentacles out




I also saw this. Not sure if it's the same or not as it's on the side of a rock and I can't get a good pic from that side.




Also, what is this?

 

the skeletons kinda look like these, but I don't know if their tentacles are clear like that...
from:http://www.liveaquaria.com/product/prod_display.cfm?c=597 321 428&pcatid=428

 

the tentacles remind me of a glass anemone
http://ac4.yt-thm-a02.yimg.com/image/0ea5bed5ca323588

and this looks like a little piece of pink birdsnest


http://ac4.yt-thm-a01.yimg.com/image/d6b756968999aa5c

 

Are they bad? Do you think these are something I need to worry about, and get rid of?

 

WOW!!!! im not sure but, i like what i see. i love a bonus. dont think its an anemone